Hi everybody. I'm pretty new at electronics. I am an apprentice electrician so I understand most of whats been said here.
I have been doing research on a strobe circuit that could flash one group of leds 3 or 4 times then flash a second group the same amount of time. I have attempted to use the 555 timer with a 4017 decade counter. It will work, but I found this other circuit that does the same thing but without the chips.
I have been trying to re-produce this circuit but can't seem to do it. I think it has a semiconductor installed. I have attached some pictures of the circuit I'm trying to re produce. On the back side of the circuit board there was a black epoxy blob that I removed to figure out whats happening.
Inside the blob there is a tiny square something that does conduct but can't get an ohm reading through it.
It seems to be a really simple circuit except for the black blob part. Any ideas?
Lights flash simultaneously or Lights flash one after the other
I put the circuit operating on youtube:
http://www.youtube.com/watch?v=MiFlF2FgzOA
This circuit uses:
(2) S8550 transistors,
100uF cap,
(2) diodes,
I think one zener diode,
electrolytic cap it say 104 on it,
(2) 1.6k resistors connected to transistors,
560 ohm res. located next to cap,
and a 5.6k resistor next to the 2 diodes.
I have been doing research on a strobe circuit that could flash one group of leds 3 or 4 times then flash a second group the same amount of time. I have attempted to use the 555 timer with a 4017 decade counter. It will work, but I found this other circuit that does the same thing but without the chips.
I have been trying to re-produce this circuit but can't seem to do it. I think it has a semiconductor installed. I have attached some pictures of the circuit I'm trying to re produce. On the back side of the circuit board there was a black epoxy blob that I removed to figure out whats happening.
Inside the blob there is a tiny square something that does conduct but can't get an ohm reading through it.
It seems to be a really simple circuit except for the black blob part. Any ideas?
Lights flash simultaneously or Lights flash one after the other
I put the circuit operating on youtube:
http://www.youtube.com/watch?v=MiFlF2FgzOA
This circuit uses:
(2) S8550 transistors,
100uF cap,
(2) diodes,
I think one zener diode,
electrolytic cap it say 104 on it,
(2) 1.6k resistors connected to transistors,
560 ohm res. located next to cap,
and a 5.6k resistor next to the 2 diodes.
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